title: Multidimensional analysis of the learning curve for laparoscopic resection in rectal cancer.
abstract: BACKGROUND
  We attempted to assess the learning curve for laparoscopic resection for rectal cancer.
  
  
  METHODS
  We included 381 patients who underwent laparoscopic resection for rectal cancer between December 2002 and December 2007. The operative experience was divided into four periods according to numbers of operations and significant changes in main surgical results.
  
  
  RESULTS
  Operative time decreased significantly after 90 operations. The overall anastomotic leakage rate was 3.7%; 14.6% for the first 50 patients and 5.4% for the following 40 patients. The overall conversion rate was 2.9%, 4-6% during the first and second periods, but decreasing thereafter. The number of harvested lymph nodes and distal resection margin was within an acceptable range during the entire period. For the patients with stage I-III tumors, the local recurrence rate was 4.4% and the overall recurrence rate was 22.9%. The local recurrence rate was 8.9% initially and decreasing to 1.4% after the second period. The cumulative incidence of local recurrence decreased to less than 7% after 120 patients and to less than 5% after 180 cases.
  
  
  CONCLUSIONS
  The learning curve for laparoscopic surgery for rectal cancer changed over time. Moreover, the learning curve for oncological safety was longer than that for operative safety.
authors.affiliation: Department of Surgery, School of Medicine, Kyungpook National University, Daegu, Korea.
authors.forename: In Ja
authors.initials: IJ
authors.lastname: Park
authors.forename: Gyu-Seog
authors.initials: GS
authors.lastname: Choi
authors.forename: Kyoung Hoon
authors.initials: KH
authors.lastname: Lim
authors.forename: Byung Mo
authors.initials: BM
authors.lastname: Kang
authors.forename: Soo Han
authors.initials: SH
authors.lastname: Jun
mesh_terms: D000368:Aged; D001003:Anal Canal / Q000601:surgery; D000714:Anastomosis, Surgical / Q000009:adverse effects; D002983:Clinical Competence; D015331:Cohort Studies; D003106:Colon / Q000601:surgery; D005260:Female; D006801:Humans; D010535:Laparoscopy / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology*; D012004:Rectal Neoplasms / Q000473:pathology / Q000601:surgery*; D012189:Retrospective Studies; D013997:Time Factors